This invention relates to an encoding/decoding technology for a plurality of image data series. The invention relates to a technology that will be effective when applied to a processing for multi-streams for displaying both reception image and transmission image on a terminal in a television telephone system, for example.
The International Standard of image signals includes MPEG-4 (ISO14496-2) that handles encoding data of a plurality of image series. The MPEG-4 can decode a plurality of encoded image data series corresponding to a plurality of objects and can synthesize and display them.
To decode the image data of a plurality of image series, the number of decoders corresponding to the number of image series simultaneously handled must be disposed or the number of control registers necessary for simultaneously handling the image series must be disposed in parallel with one another inside one decoder. In either case, the scale of the apparatus is likely to increase. To solve this problem, JP-A-2002-171523 (FIGS. 5 and 8; corresponding to Ishida et al U.S. 2002/0041714A1) provides an image decoder that arranges save areas of decoding information for decoding image data of a plurality of image series, executes a decoding processing by use of a single decoder and can cope with the increase of the number of the image series to be simultaneously decoded through a relatively simple construction.